Joining system and method for floor boards and boards therefor

ABSTRACT

The invention relates to a joining system and method for floorboards, e.g. for parquetry. The joining system comprises floor boards intended to be joined with each other, wherein a first board (A) has a protrusion fitting into a recess in a second board (B). The protrusion on the first board comprises hooks ( 1 ) with intermediate slots ( 2 ) or chamfers. The recess ( 11 ) in the second board (B) is delimited on the top side by a solid edge ( 3 ), and on the bottom side by an edge having heads ( 4 ) dimensioned to be inserted through the slots ( 2 ) of the first board (A). The invention will replace the traditional groove and tenon technique. By providing slots or chamfers in the protrusion corresponding to the tenon, and corresponding cuts in the lower limiting edge of the groove, the boards can be joined in a substantially vertical or transversal movement and then be locked by a horizontal movement in the longitudinal direction of the boards. At the same time, the protrusion is shaped like hooks engaging the groove. Hereby, the joining will be very simple to perform, whilst at the same time providing a strong joint.

FIELD OF THE INVENTION

[0001] The present invention relates to a joining system and method for floorboards, panels and sheaves, but foremost for parquetry. The invention will replace the traditional groove and tenon technique. By providing slots or chamfers in the protrusion corresponding to the tenon, and corresponding cuts in the lower limiting edge of the groove, the boards can be joined in a substantially vertical or transversal movement and then be locked by a horizontal movement in the longitudinal direction of the boards. At the same time, the protrusion is hook-shaped so that the protrusion engages the groove. Through this, the joining will be very simple to perform, whilst at the same time providing a strong joint.

STATE OF THE ART

[0002] The traditional groove and tenon technique for floorboards has been known in the art for a long time. Furthermore, there are a number of alternative technical solutions available with various shapes of protrusions and recesses. Through giving the protrusions various hook-like shapes, a firmer locking has been achieved than with the groove and tenon. During assembly, the boards are angled in relation to each other, joined and pivoted to achieve a planar floor surface and a simultaneous locking. Examples of this technique are e.g. shown in WO 94/26999, U.S. Pat. No. 5,797,237 and U.S. Pat. No. 6,006,486. It is also known to complete the locking with separate auxiliary locking elements. This is illustrated e.g. in SE B 512 290.

[0003] However, it is not always easy to join the boards, as the entire length of a protrusion on a board has to be fitted into the recess of an existing, already laid-down board, before the new board can be pivoted and locked into its final position. This is especially difficult if the board is warped and not entirely straight, and too long for one person to control both ends simultaneously.

[0004] The present inventor has realised that the joining will be simpler if the necessary angle between the boards is reduced and the boards can be joined with an almost vertical movement. In another embodiment the boards can be joined with an almost transversal movement. This is achieved by providing milled slots or chamfers in the protrusions and in the lower edge of the recesses, allowing the board to be joined to be inserted into the already laid-down board more or less from above or from the side. The new board can then be displaced longitudinally to obtain the final locking thereof.

[0005] The invention allows for simple floor-laying that can easily be performed by one person. At the same time, the board manufacturing process is not made notably more complicated.

SUMMARY OF THE INVENTION

[0006] The invention thus relates to a Joining system for floorboards, comprising boards intended to be joined together. The first board has a protrusion fitting into a recess in the second board.

[0007] According to the invention, the protrusion on the first board exhibits hooks or hook-shaped portions with intermediate slots or chamfers, and the recess of the second board is delimited in the upwards direction by a solid edge, and in the downwards direction by an edge with heads, sized so as to enable insertion through the slots in the first board.

[0008] Preferably, the lower edge of the recess has shoulders between the heads.

[0009] The invention also relates to a corresponding board for such a joining system.

[0010] The invention also relates to corresponding joining methods.

[0011] The invention is defined in the appended claims 1, 11, 21, 30, 39, 41 and 43, whereas preferred embodiments are described in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The invention will be described in further detail below, with reference to the enclosed drawings, of which:

[0013]FIG. 1 is a partial cross section view of two boards, taken from the short side thereof, not joined together, according to one embodiment of the present invention.

[0014]FIG. 2 is a view similar to FIG. 1, with the boards joined.

[0015]FIG. 3 is a perspective view, illustrating the recess on one long side of a board of the first embodiment.

[0016]FIG. 4 is a perspective view from the other side, showing the hooks on the other long side of a board of the first embodiment.

[0017]FIG. 5 is a view corresponding to FIG. 3, with joined boards before being diplaced to the final position.

[0018]FIG. 6 is a view corresponding to FIG. 4, with joined boards in the final position.

[0019]FIG. 7 is a partial cross section view of two boards similar to FIG. 1 of a second embodiment of the present invention.

[0020]FIG. 8 is a view similar to FIG. 7, with the boards joined.

[0021]FIG. 9 is a perspective view, illustrating the recess on one long side of a board of the second embodiment.

[0022]FIG. 10 is a perspective view from the other side, showing the hooks on the other long side of a board of the second embodiment.

[0023]FIG. 11 is a partial cross section view of two boards similar to FIG. 1 of a third embodiment of the present invention.

[0024]FIG. 12 is a view similar to FIG. 11, with the boards joined.

[0025]FIG. 13 is a perspective view illustrating the recess on one long side of a board of the third embodiment.

[0026]FIG. 14 is a perspective view from the other side, showing the hooks on the other long side of a board of the third embodiment.

[0027]FIG. 15 is a partial cross section view of two boards similar to FIG. 1 of a fourth embodiment of the present invention.

[0028]FIG. 16 is a view similar to FIG. 15, with the boards joined.

[0029]FIG. 17 is a perspective view illustrating the recess on one long side of a board of the fourth embodiment.

[0030]FIG. 18 is a perspective view from the other side, showing the chamfers on the other long side of a board of the fourth embodiment.

[0031]FIG. 19 is a partial cross section view of two boards similar to FIG. 1 of a fifth embodiment of the present invention.

[0032]FIG. 20 is a view similar to FIG. 18, with the boards joined.

[0033]FIG. 21 is a perspective view illustrating the recess on one long side of a board of the fifth embodiment.

[0034]FIG. 22 is a perspective view from the other side, showing the chamfers on the other long side of a board of the fifth embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0035] The invention will be illustrated by means of embodiments where the floorboards are made of wood. It should be understood that other materials, such as laminates, plastic, etc. could be used just as well.

[0036] The term hook is generally intended to mean a projection with a profiled shape the function of which is to engage a cavity. The term head is generally intended to mean a projection jutting out from a surface. The terms slot and cut are generally intended to mean a space between two hooks and two heads, respectively. The term solid is generally intended to mean a straight surface not broken by a cut. The term non-solid is generally intended to mean a surface broken by a cut or slot. The terms horizontal and vertical are used for describing directions in relation to a board that is lying on a horizontal surface as in a typical floor. However, as a matter of course, the invention is equally applicable to boards for wall and ceiling panels in any direction.

[0037] In FIGS. 1 and 2, two boards A and B are shown in a cross sectional view from their short sides. The boards have an upper wear layer 8 of hardwood and a carrier layer of simpler wood, as is conventional. It should be understood that the boards A and B are identical, but FIGS. 1 and 2 show only the joint between a right hand long side of board A and a left hand long side of board B.

[0038] See also FIGS. 3, 4, 5 and 6, showing perspective views of the boards. Instead of a traditional tenon, board A exhibits hooks 1 with intermediate milled slots or cuts 2. Board B has a recess 11, corresponding to a traditional groove. The recess is delimited on the top side by a solid edge 3, and on the bottom side by a non-solid edge comprising heads 4 with intermediate milled cuts. Preferably, these cuts do not extend to the full depth of the recess 11 but there is a shoulder 7 remaining. The function of the shoulder 7 will be described below.

[0039] The joining is performed as follows:

[0040] Board A is laid in place and is to be joined with the next board B.

[0041] Board B is fitted from above in such a way that the heads 4 will pass through the slots 2 of board A. Through angling board B somewhat, and holding it at an appropriate distance from board A, the shoulders 7 will be allowed to pass the hooks.

[0042] Eventually, the solid edge 3 of board B will abut the top side 5 of the hooks 1, and the shoulders 7 can be pushed under the hooks 1 through pivoting and pushing the two boards together.

[0043] Subsequently, board B can be displaced longitudinally, into its correct position in relation to the walls and the other floorboards. The heads 4 will thereby also be displaced to a location below the hooks 1, to form a strong joint. The joint may be further reinforced by glue, applied e.g. to the top side 5 of the hooks before mounting board B. The shoulders 7 may for example be about 2 mm long. It is also conceivable to mill away the shoulders 7 completely, down to the bottom of the recess. Board B can then be laid down entirely vertically, but at the same time, the joint will be weakened, as the entire head 4 generally will not happen to be located below a hook 1.

[0044] The top side 5 of the hook 1 is preferably angled, as is the matching underside 6 of the recess 11. A suitable angle is about 45°. The hooks may also have other profiled shapes than the configuration shown with straight edges and a flat exterior end surface, e.g. convexely or concavely rounded shapes or other curved and hook-shaped configurations of which some embodiments are described below. The recess will have a more or less complementary shape. The main point is that the configuration should result in that the boards A and B cannot be pulled away from each other sideways without turning after having been joined.

[0045] In FIGS. 7 to 10 a second embodiment is shown. Corresponding parts are denoted by the same reference numerals as in FIGS. 1 to 6 with the FIG. 2 added in front. In this embodiment the shape of the top of the hooks 21 and the corresponding downwardly facing inside of the edge 23 have a different design. Instead of being straight and angled the sides are configured with horizontal surfaces so that the hook 21 has a flat top 25 and the inner side a correspondingly flat abutment surface 26. If the boards should move relative each other horizontally, they will be guided by both the top flat contact surface at 25 and 26, and by the lower flat contact surface at the lower side of the hook 21 and the corresponding upwardly facing inner side of the edge 23. The guiding results in that there will be no difference in height beween the upper surfaces of the boards if the hook 21 should move relative the recess 211.

[0046] The shoulder 27 is shown straight in the figures but may also have a rounded upper edge. This will facilitate the joining but also result in a slightly looser joint.

[0047] The joining is more similar to the conventional method and is performed as follows:

[0048] Board 2A is laid in place and is to be joined with the next board 2B.

[0049] Board 2B is laid on the existing ground next to board 2A in such a way that the heads 24 are located straight in front of the slots 22 of board 2A and the hooks 21 straight in front of the shoulders 27. It is now easy to push or knock the boards is together e.g. by means of a mallet and a block, similar to the case with the traditional groove and tenon. Thereby the hooks 21 will pass under the solid edge 23, past the shoulders 27 and into the recess 211.

[0050] Just when the hook 21 passes under the edge 23 a small angling or lift will occur between the boards to allow the passage. However, this occurs automatically and is hardly noticable for the floor-layer.

[0051] Thereafter, board 2B can be displaced longitudinally just as before, into its correct position in relation to the walls and the other floorboards. The heads 24 will thereby also be displaced to a location below the hooks 21, to form a strong joint. The joint may be further reinforced by glue, applied e.g. to the top side 25 of the hooks before mounting board 2B. The shoulders 27 may for example be about 2 mm long.

[0052] A third embodiment is shown in FIGS. 11 to 14. Corresponding parts are denoted by the same reference numerals as in FIGS. 1 to 6 with the FIG. 3 added in front. Here, the hook 31 is instead provided with a downwardly facing projection 315 fitting in a corresponding groove 316 in the upwardly facing inner side of the recess 311. The joining is performed in essentially the same way as in the above second embodiment.

[0053] A fourth embodiment is shown in FIGS. 15 to 18. Corresponding parts are denoted by the same reference numerals as in FIGS. 1 to 6 with the FIG. 4 added in front. Here, board 4A is provided with a protrusion but the slots are not milled through the protrusion but chamfered as shown at 48. Between the chamfers 48 the protrusion is shaped like a whole hook 41. The protrusion has an unbroken solid top edge 42 (FIG. 18) with the same flat top 45 as in the second embodiment above. Board 4B has a shape identical with the second embodiment having a solid edge 43, a recess 411, heads 44, and shoulders 47. The shoulder 47 is shown straight in the figures but may also have a rounded upper edge. This will facilitate the joining but also result in a slightly looser joint.

[0054] The joining is similar to the method used with the second and third embodiments and is performed as follows:

[0055] Board 4A is laid in place and is to be joined with the next board 4B.

[0056] Board 4B is laid on the existing ground next to board 4A in such a way that the heads 44 are located straight in front of the chamfers 48 of board 4A and the hook-shaped portions 41 straight in front of the shoulders 47. It is now easy to push or knock the boards together by means of a mallet and a block, similar to the case with the traditional groove and tenon. Thereby the hook-shaped portions 41 will pass under the solid edge 43, past the shoulders 47 and into the recess 411. The heads 44 do not need a slot but will slid under the chamfers 48.

[0057] Just when the hook 41 passes under the edge 43 a small angling or lift will occur between the boards to allow the passage as before.

[0058] Thereafter, board 4B can be displaced longitudinally just as before, into its correct position in relation to the walls and the other floorboards. The heads 44 will thereby also be displaced to a location below the hooks 41, to form a strong joint.

[0059] The joint may be further reinforced by glue, applied e.g. to the top side 45 of the hooks before mounting board 4B. The shoulders 47 may for example be about 2 mm long.

[0060] A fifth embodiment is shown in FIGS. 19 to 22. Corresponding parts are denoted by the same reference numerals as in FIGS. 1 to 6 with the FIG. 5 added in front. Here, just as in the fourth embodiment the board 5A is provided with a protrusion where the slots are not milled through the protrusion but chamfered as shown at 58. Between the chamfers 58 the protrusion is shaped with a downwardly facing projection 515 fitting in a corresponding groove 516 in the upwardly facing inner side of the recess 511 as in the third embodiment. The protrusion has an unbroken solid top edge with the same shape as in the third embodiment above. Board 5B has a shape identical with the third embodiment. The shoulder 57 is shown straight in the figures but may also have a rounded upper edge. This will facilitate the joining but also result in a slightly looser joint.

[0061] The joining is performed in essentially the same way as in the above second embodiment the heads with the grooves 516 sliding under the chamfers 58.

[0062] After the joining, a small clearance will remain between the boards A and B in the carrier layer 9, as may be seen from FIG. 2. The wear layer 8 should preferably not have any remaining gap between the boards. If the boards, after the joining, should become warped, or if the underlying floor is uneven, the boards can pivot in relation to one another about a point located at the top side 5, 25, 45 of the hooks and the underside 6, 26, 46 of the recess 11, 211, 411. It is advantageous for this point to be located as high as possible, thus avoiding the creation of any gap in the wear layer if the angle between the boards is changed.

[0063] In the illustrated embodiments, the widths of the hooks and the intermediate slots or chamfers are the same. This may be varied as long as the heads have a width corresponding to the slots or chamfers. The heads (and the hooks) should be about 8 mm wide and the slots or chamfers (and the shoulders) should be about 10 mm wide. As the tenon at the short side is 6 mm, the displacement will be at least 6 mm. If the heads are made wider, e.g. 20 mm, the total surface locking the boards will be reduced.

[0064] The short sides of the boards of all the embodiments may be provided with conventional groove-and-tenon joints (or another well known system). This is illustrated in connection with the first embodiment in FIGS. 3, 4, 5 and 6 by a groove 10. The corresponding tenon is located at the other short end and thus is not visible.

[0065] The illustrated embodiments may be varied e.g. through modification of the thickness of the wear and carrier layers, the angles and configuration of the hook, the width and the length of the boards, etc., all of which should be obvious to a person skilled in the art. The scope of the invention will only be limited by the appended claims. 

1. A joining system for floor boards, comprising boards intended to be joined with each other, wherein a first board has a protrusion fitting into a recess in a second board, wherein said protrusion on the first board comprises hooks with intermediate slots; and said recess in the second board being delimited on the top side by a solid edge; and on the bottom side by an edge having heads; said hooks on the first board being dimensioned to be able to pass between the heads on the second board.
 2. A joining system according to claim 1, wherein the hooks exhibit profiled top sides; and the solid edge having a correspondingly profiled underside.
 3. A joining system according to claim 2, wherein the top side of the hooks is configured with a straight angled top; and the solid edge is configured with a correspondingly shaped downwardly facing inner side.
 4. A joining system according to claim 2, wherein the top side of the hooks is configured with a flat top; and the solid edge is configured with a correspondingly shaped downwardly facing inner side.
 5. A joining system according to claim 2, wherein the lower side of the hooks is configured with a projection; and the solid edge is configured with a correspondingly shaped upwardly facing inner side.
 6. A joining system according to claim 1, wherein the bottom edge of said recess exhibits shoulders between the heads.
 7. A joining system according to claim 6, wherein said shoulders have a rounded upper edge.
 8. A joining system according to claim 1, wherein the hooks, the slots and the heads have substantially the same size in the longitudinal direction of the boards.
 9. The joining system according to claim 8, wherein the heads are slightly narrower than the slots.
 10. A joining system according to claim 1, wherein the short sides of the boards are provided with grooves and tenons fitting into each other.
 11. A board for a joining system, having a protrusion on a first long side of the board and a recess on a second long side of the board, said protrusion fitting into said recess, wherein said protrusion on said first long side comprises hooks with intermediate slots; and said recess in said second long side being delimited on the top side by a solid edge, and on the bottom side by an edge having heads, said hooks being dimensioned to be able to be pass between heads on another identical board, thus allowing identical such boards to be joined with each other.
 12. A board according to claim 11, wherein the hooks exhibit profiled top sides and by the solid edge having a correspondingly profiled underside.
 13. A board according to claim 12, wherein the top side of the hooks is configured with a straight angled top; and the solid edge is configured with a correspondingly shaped downwardly facing inner side.
 14. A board according to claim 12, wherein the top side of the hooks is configured with a flat top; and the solid edge is configured with a correspondingly shaped downwardly facing inner side.
 15. A board according to claim 12, wherein the lower side of the hooks is configured with a projection; and the solid edge is configured with a correspondingly shaped upwardly facing inner side.
 16. A board according to claim 11, wherein the bottom edge of said recess exhibits shoulders between the heads.
 17. A board according to claim 16, wherein said shoulders have a rounded upper edge.
 18. A board according to claim 11, wherein the hooks, the slots and the heads have substantially the same size in the longitudinal direction of the boards.
 19. A board according to claim 18, wherein the heads are slightly narrower than the slots.
 20. A board according to claim 11, wherein the short sides of the boards are provided with grooves and tenons, allowing identical such boards to be joined with each other.
 21. A joining system for floor boards, comprising boards intended to be joined with each other, wherein a first board has a protrusion fitting into a recess in a second board, wherein said protrusion on the first board having chamfers with intermediate hook-shaped portions and having a solid top edge; and said recess in the second board being delimited on the top side by a solid edge; and on the bottom side by an edge having heads; said hook-shaped portions on the first board being dimensioned to be able to pass between the heads on the second board.
 22. A joining system according to claim 21, wherein the hook-shaped portions exhibit profiled top sides; and the solid edge of the recess having a correspondingly profiled underside.
 23. A joining system according to claim 22, wherein the top side of the hooks is configured with a flat top; and the solid edge of the recess is configured with a correspondingly shaped downwardly facing inner side.
 24. A joining system according to claim 22, wherein the lower side of the hooks is configured with a projection; and the solid edge of the recess is configured with a correspondingly shaped upwardly facing inner side.
 25. A joining system according to claim 21, wherein the bottom edge of said recess exhibits shoulders between the heads.
 26. A joining system according to claim 25, wherein said shoulders have a rounded upper edge.
 27. A joining system according to claim 21, wherein the hook-shaped portions, the camfers and the heads have substantially the same size in the longitudinal direction of the boards.
 28. The joining system according to claim 27, wherein the heads are slightly narrower than the chamfers.
 29. A joining system according to claim 21, wherein the short sides of the boards are provided with grooves and tenons fitting into each other.
 30. A board for a joining system, having a protrusion on a first long side of the board and a recess on a second long side of the board, said protrusion fitting into said recess, wherein said protrusion on said first long side comprises chamfers with intermediate hook-shaped portions; and said recess in said second long side being delimited on the top side by a solid edge, and on the bottom side by an edge having heads, said hook-shaped portions being dimensioned to be able to be pass between heads on another identical board, thus allowing identical such boards to be joined with each other.
 31. A board according to claim 30, wherein the protrusion exhibits a profiled top side and by the solid edge of the recess having a correspondingly profiled underside.
 32. A board according to claim 31, wherein the top side of the protrusion is configured with a flat top; and the solid edge is configured with a correspondingly shaped downwardly facing inner side.
 33. A board according to claim 30, wherein the lower side of the hook-shaped portions is configured with a projection; and the solid edge of the recess is configured with a correspondingly shaped upwardly facing inner side.
 34. A board according to claim 30, wherein the bottom edge of said recess exhibits shoulders between the heads.
 35. A board according to claim 34, wherein said shoulders have a rounded upper edge.
 36. A board according to claim 30, wherein the hook-shaped portions, the chamfers and the heads have substantially the same size in the longitudinal direction of the board.
 37. A board according to claim 36, wherein the heads are slightly narrower than the chamfers.
 38. A board according to claim 30, wherein the short sides of the boards are provided with grooves and tenons, allowing identical such boards to be joined with each other.
 39. A method of joining floor boards, utilizing boards intended to be joined with each other, wherein a first board has a protrusion fitting into a recess in a second board, said protrusion on the first board comprising hooks with intermediate slots; and said recess in the second board being delimited on the top side by a solid edge; and on the bottom side by an edge having heads and shoulders between the heads; said hooks on the first board being dimensioned to be able to pass between the heads on the second board, comprising the steps of: when the first board is laid in place and to be joined with the second board, fitting the second board from above in such a way that the heads will pass through the slots of the first board; angling the second board somewhat, and holding it at an appropriate distance from the first board, so that the shoulders will be allowed to pass the hooks; moving the second board downwards until, the solid edge of the second board abuts the top side of the hooks; pushing the shoulders under the hooks through pivoting and pushing the two boards together; displacing the second board longitudinally.
 40. A method of joining floor boards according to claim 39, wherein the joint is reinforced by glue, applied to the top side of the hooks before mounting the second board.
 41. A method of joining floor boards, utilizing boards intended to be joined with each other, wherein a first board has a protrusion fitting into a recess in a second board, said protrusion on the first board comprising hooks with intermediate slots; and said recess in the second board being delimited on the top side by a solid edge; and on the bottom side by an edge having heads and shoulders between the heads; said hooks on the first board being dimensioned to be able to pass between the heads on the second board, comprising the steps of: when the first board is laid in place and to be joined with the second board, laying the second board on the existing ground next to the first board in such a way that the heads are located straight in front of the slots of the first board and the hooks straight in front of the shoulders; pushing the boards together so that the hooks pass under the solid edge, past the shoulders and into the recess; displacing the second board longitudinally.
 42. A method of joining floor boards according to claim 41, wherein the joint is reinforced by glue, applied to the top side of the hooks before mounting the second board.
 43. A method of joining floor boards, utilizing boards intended to be joined with each other, wherein a first board has a protrusion fitting into a recess in a second board, said protrusion on the first board comprising chamfers with intermediate hook-shaped portions; and said recess in the second board being delimited on the top side by a solid edge; and on the bottom side by an edge having heads and shoulders between the heads; said hook-shaped portions on the first board being dimensioned to be able to pass between the heads on the second board, comprising the steps of: when the first board is laid in place and to be joined with the second board, laying the second board on the existing ground next to the first board in such a way that the heads are located straight in front of the chamfers of the first board and the hook-shaped portions straight in front of the shoulders; pushing the boards together so that the hook-shaped portions pass under the solid edge, past the shoulders and into the recess; displacing the second board longitudinally.
 44. A method of joining floor boards according to claim 43, wherein the joint is reinforced by glue, applied to the top side of the protrusion before mounting the second board. 